A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The Last Glacial Period ended about 15,000 years ago.[1] The Holocene is the current interglacial. A time with no glaciers on Earth is considered a greenhouse climate state.[2][3][4]
Glacial and interglacial cycles as represented by atmospheric CO2, measured from ice core samples going back 800,000 years. The stage names are part of the North American and the European Alpine subdivisions. The correlation between both subdivisions is tentative.
Within the Quaternary, which started about 2.6 million years before present, there have been a number of glacials and interglacials.[5] At least eight glacial cycles have occurred in the last 740,000 years alone.[6]
The Penultimate Glacial Period (PGP) is the glacial period that occurred before the Last Glacial Period. It began about 194,000 years ago and ended 135,000 years ago, with the beginning of the Eemian interglacial.[7]
The last glacial period was the most recent glacial period within the Quaternary glaciation at the end of the Pleistocene, and began about 110,000 years ago and ended about 11,700 years ago.[1] The glaciations that occurred during the glacial period covered many areas of the Northern Hemisphere and have different names, depending on their geographic distributions: Wisconsin (in North America), Devensian (in Great Britain), Midlandian (in Ireland), Würm (in the Alps), Weichsel (in northern Central Europe), Dali (in East China), Beiye (in North China), Taibai (in Shaanxi) Luoji Shan (in southwest Sichuan), Zagunao (in northwest Sichuan), Tianchi (in the Tian Shan) Jomolungma (in the Himalayas), and Llanquihue (in Chile). The glacial advance reached the Last Glacial Maximum about 26,500 BP. In Europe, the ice sheet reached Northern Germany. Over the last 650,000 years, there have been on average seven cycles of glacial advance and retreat.
Since orbital variations are predictable,[8] computer models that relate orbital variations to climate can predict future climate possibilities. Work by Berger and Loutre suggests that the current warm climate may last another 50,000 years.[9] The amount of heat trapping (greenhouse) gases being emitted into the Earth's oceans and its atmosphere may delay the next glacial period by an additional 50,000 years.[10][11]
Referencesedit
^ abJ. Severinghaus; E. Brook (1999). "Abrupt Climate Change at the End of the Last Glacial Period Inferred from Trapped Air in Polar Ice". Science. 286 (5441): 930–4. doi:10.1126/science.286.5441.930. PMID 10542141.
^Bralower, T.J.; Premoli Silva, I.; Malone, M.J. (2006). Bralower, T.J; Premoli Silva, I; Malone, M.J (eds.). "Leg 198 Synthesis : A Remarkable 120-m.y. Record of Climate and Oceanography from Shatsky Rise, Northwest Pacific Ocean". Proceedings of the Ocean Drilling Program. Initial Reports. Proceedings of the Ocean Drilling Program. Proceedings of the Ocean drilling program. 198: 47. doi:10.2973/odp.proc.ir.198.2002. ISSN 1096-2158. Retrieved April 9, 2014.
^Christopher M. Fedo; Grant M. Young; H. Wayne Nesbitt (1997). "Paleoclimatic control on the composition of the Paleoproterozoic Serpent Formation, Huronian Supergroup, Canada: a greenhouse to icehouse transition". Precambrian Research. Elsevier. 86 (3–4): 201. Bibcode:1997PreR...86..201F. doi:10.1016/S0301-9268(97)00049-1.
^Miriam E. Katz; Kenneth G. Miller; James D. Wright; Bridget S. Wade; James V. Browning; Benjamin S. Cramer; Yair Rosenthal (2008). "Stepwise transition from the Eocene greenhouse to the Oligocene icehouse". Nature Geoscience. Nature. 1 (5): 329. Bibcode:2008NatGe...1..329K. doi:10.1038/ngeo179.
^Gibbard, P.; van Kolfschoten, T. (2004). "Chapter 22: The Pleistocene and Holocene Epochs" (PDF). In Gradstein, F. M.; Ogg, James G.; Smith, A. Gilbert (eds.). A Geologic Time Scale 2004. Cambridge: Cambridge University Press. ISBN978-0-521-78142-8.
^Augustin, Laurent; et al. (2004). "Eight glacial cycles from an Antarctic ice core". Nature. 429 (6992): 623–8. Bibcode:2004Natur.429..623A. doi:10.1038/nature02599. PMID 15190344.
^Nehme, Carole; Verheyden, Sophie; Breitenbach, Sebastian F.M.; Gillikin, David P.; et al. (July 2018). "Climate Dynamics During the Penultimate Glacial Period Recorded in a Speleothem from Kanaan Cave, Lebanon (central Levant)" (PDF). Quaternary Research. 90 (1): 10–25. Bibcode:2018QuRes..90...10N. doi:10.1017/qua.2018.18. S2CID 134924228.
^F. Varadi; B. Runnegar; M. Ghil (2003). "Successive Refinements in Long-Term Integrations of Planetary Orbits". The Astrophysical Journal. 592 (1): 620–630. Bibcode:2003ApJ...592..620V. doi:10.1086/375560.
^Berger A, Loutre MF (2002). "Climate: An exceptionally long interglacial ahead?". Science. 297 (5585): 1287–8. doi:10.1126/science.1076120. PMID 12193773. S2CID 128923481.
^Tyrrell, Toby (16 November 2007). "Calcium Carbonate Cycling in Future Oceans and its Influence on Future Climates". Journal of Plankton Research. 30 (2): 141–156. doi:10.1093/plankt/fbm105.
^Ganopolski, A.; Winkelmann, R.; Schellnhuber, H. J. (14 January 2016). "Critical Insolation–CO2 Relation for Diagnosing Past and Future Glacial Inception". Nature. 529 (7585): 200–203. Bibcode:2016Natur.529..200G. doi:10.1038/nature16494. PMID 26762457. S2CID 4466220.
External linksedit
Look up glaciation in Wiktionary, the free dictionary.
January 19, 2024
glacial, period, longer, glacial, periods, film, 2002, film, glacial, period, alternatively, glacial, glaciation, interval, time, thousands, years, within, that, marked, colder, temperatures, glacier, advances, interglacials, other, hand, periods, warmer, clim. For longer glacial periods see ice age For film see Ice Age 2002 film A glacial period alternatively glacial or glaciation is an interval of time thousands of years within an ice age that is marked by colder temperatures and glacier advances Interglacials on the other hand are periods of warmer climate between glacial periods The Last Glacial Period ended about 15 000 years ago 1 The Holocene is the current interglacial A time with no glaciers on Earth is considered a greenhouse climate state 2 3 4 Contents 1 Quaternary Period 2 Penultimate Glacial Period 3 Last Glacial Period 4 Next glacial period 5 References 6 External linksQuaternary Period editMain articles Quaternary glaciation and timeline of glaciation nbsp Glacial and interglacial cycles as represented by atmospheric CO2 measured from ice core samples going back 800 000 years The stage names are part of the North American and the European Alpine subdivisions The correlation between both subdivisions is tentative Within the Quaternary which started about 2 6 million years before present there have been a number of glacials and interglacials 5 At least eight glacial cycles have occurred in the last 740 000 years alone 6 Penultimate Glacial Period editMain article Penultimate Glacial Period The Penultimate Glacial Period PGP is the glacial period that occurred before the Last Glacial Period It began about 194 000 years ago and ended 135 000 years ago with the beginning of the Eemian interglacial 7 Last Glacial Period editMain article Last Glacial Period The last glacial period was the most recent glacial period within the Quaternary glaciation at the end of the Pleistocene and began about 110 000 years ago and ended about 11 700 years ago 1 The glaciations that occurred during the glacial period covered many areas of the Northern Hemisphere and have different names depending on their geographic distributions Wisconsin in North America Devensian in Great Britain Midlandian in Ireland Wurm in the Alps Weichsel in northern Central Europe Dali in East China Beiye in North China Taibai in Shaanxi Luoji Shan in southwest Sichuan Zagunao in northwest Sichuan Tianchi in the Tian Shan Jomolungma in the Himalayas and Llanquihue in Chile The glacial advance reached the Last Glacial Maximum about 26 500 BP In Europe the ice sheet reached Northern Germany Over the last 650 000 years there have been on average seven cycles of glacial advance and retreat Next glacial period editSee also Milankovitch cycles Since orbital variations are predictable 8 computer models that relate orbital variations to climate can predict future climate possibilities Work by Berger and Loutre suggests that the current warm climate may last another 50 000 years 9 The amount of heat trapping greenhouse gases being emitted into the Earth s oceans and its atmosphere may delay the next glacial period by an additional 50 000 years 10 11 References edit a b J Severinghaus E Brook 1999 Abrupt Climate Change at the End of the Last Glacial Period Inferred from Trapped Air in Polar Ice Science 286 5441 930 4 doi 10 1126 science 286 5441 930 PMID 10542141 Bralower T J Premoli Silva I Malone M J 2006 Bralower T J Premoli Silva I Malone M J eds Leg 198 Synthesis A Remarkable 120 m y Record of Climate and Oceanography from Shatsky Rise Northwest Pacific Ocean Proceedings of the Ocean Drilling Program Initial Reports Proceedings of the Ocean Drilling Program Proceedings of the Ocean drilling program 198 47 doi 10 2973 odp proc ir 198 2002 ISSN 1096 2158 Retrieved April 9 2014 Christopher M Fedo Grant M Young H Wayne Nesbitt 1997 Paleoclimatic control on the composition of the Paleoproterozoic Serpent Formation Huronian Supergroup Canada a greenhouse to icehouse transition Precambrian Research Elsevier 86 3 4 201 Bibcode 1997PreR 86 201F doi 10 1016 S0301 9268 97 00049 1 Miriam E Katz Kenneth G Miller James D Wright Bridget S Wade James V Browning Benjamin S Cramer Yair Rosenthal 2008 Stepwise transition from the Eocene greenhouse to the Oligocene icehouse Nature Geoscience Nature 1 5 329 Bibcode 2008NatGe 1 329K doi 10 1038 ngeo179 Gibbard P van Kolfschoten T 2004 Chapter 22 The Pleistocene and Holocene Epochs PDF In Gradstein F M Ogg James G Smith A Gilbert eds A Geologic Time Scale 2004 Cambridge Cambridge University Press ISBN 978 0 521 78142 8 Augustin Laurent et al 2004 Eight glacial cycles from an Antarctic ice core Nature 429 6992 623 8 Bibcode 2004Natur 429 623A doi 10 1038 nature02599 PMID 15190344 Nehme Carole Verheyden Sophie Breitenbach Sebastian F M Gillikin David P et al July 2018 Climate Dynamics During the Penultimate Glacial Period Recorded in a Speleothem from Kanaan Cave Lebanon central Levant PDF Quaternary Research 90 1 10 25 Bibcode 2018QuRes 90 10N doi 10 1017 qua 2018 18 S2CID 134924228 F Varadi B Runnegar M Ghil 2003 Successive Refinements in Long Term Integrations of Planetary Orbits The Astrophysical Journal 592 1 620 630 Bibcode 2003ApJ 592 620V doi 10 1086 375560 Berger A Loutre MF 2002 Climate An exceptionally long interglacial ahead Science 297 5585 1287 8 doi 10 1126 science 1076120 PMID 12193773 S2CID 128923481 Tyrrell Toby 16 November 2007 Calcium Carbonate Cycling in Future Oceans and its Influence on Future Climates Journal of Plankton Research 30 2 141 156 doi 10 1093 plankt fbm105 Ganopolski A Winkelmann R Schellnhuber H J 14 January 2016 Critical Insolation CO2 Relation for Diagnosing Past and Future Glacial Inception Nature 529 7585 200 203 Bibcode 2016Natur 529 200G doi 10 1038 nature16494 PMID 26762457 S2CID 4466220 External links edit nbsp Look up glaciation in Wiktionary the free dictionary Retrieved from https en wikipedia org w index php title Glacial period amp oldid 1184030575, wikipedia, wiki, book, books, library,
